At my job, we have 1577 Callable type hints scattered in 1063 Python files.
For comparison, this codebase also has 2754 dict annotations and 1835 list
ones.

On Mon, Dec 20, 2021 at 8:11 AM Christopher Barker <python...@gmail.com>
wrote:

> note: I wasn't thinking -- typeshed, of course, has a lot more than the
> standard lib.  But it's still a collection of widely used somewhat general
> purpose libraries. So I think my hypothesis is still valid.
>
> -CHB
>
>
> On Sun, Dec 19, 2021 at 8:54 PM Christopher Barker <python...@gmail.com>
> wrote:
>
>> A question that came up for me is:
>>
>> How common is it to need to use Callable for type hints? particularly
>> complex versions, specifying what parameters the Callable takes? A more
>> compact and easier to read syntax is nice, but not very important if it
>> isn't used much.
>>
>> My first thought on this was that I can't remember a single time that I
>> wrote production code that took a Callable as a function parameter -- or
>> returned one -- OK maybe a few times, but it's certainly rare in my
>> production code.
>>
>> So I looked in the PEP to see if that issue was addressed, and indeed it
>> is:
>>
>> "The Callable type is widely used. For example, as of October 2021 it was
>> the fifth most common complex type in typeshed,"
>>
>> That did surprise me, but on thinking about it, maybe not so much. It
>> strikes me that Callable is most likely to be used in fairly low level,
>> general purpose functions, like map(), sort(), various functions in
>> itertools, etc. Just the sort of functions that are common in the standard
>> library, but may not so much in production code.
>>
>> I have no idea how to evaluate how common it is in production code --
>> maybe type hinting is common enough now  that PyPi could be searched -- but
>> even PyPi is a biased sample, as it is full of, by definition,
>> libraries for others' use -- i.e. general purpose tools (less general that
>> the stad lib, but still not specialty production code, which I suspect is
>> the majority of Python code out there).
>>
>> Perhaps some folks that have been type=hinting their production code
>> bases could provide anecdotal evidence.
>>
>> Anyway, if my hypothesis is correct, then it's not so bad that
>> not-so-nice syntax is required to type hint general purpose utilities.
>>
>> -CHB
>>
>> --
>> Christopher Barker, PhD (Chris)
>>
>> Python Language Consulting
>>   - Teaching
>>   - Scientific Software Development
>>   - Desktop GUI and Web Development
>>   - wxPython, numpy, scipy, Cython
>>
>
>
> --
> Christopher Barker, PhD (Chris)
>
> Python Language Consulting
>   - Teaching
>   - Scientific Software Development
>   - Desktop GUI and Web Development
>   - wxPython, numpy, scipy, Cython
> _______________________________________________
> Python-Dev mailing list -- python-dev@python.org
> To unsubscribe send an email to python-dev-le...@python.org
> https://mail.python.org/mailman3/lists/python-dev.python.org/
> Message archived at
> https://mail.python.org/archives/list/python-dev@python.org/message/LWIXFDUGRM6Z3KHI3YGV65HWXRD2S4H5/
> Code of Conduct: http://python.org/psf/codeofconduct/
>


-- 
Thanks,
Andrew Svetlov
_______________________________________________
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at 
https://mail.python.org/archives/list/python-dev@python.org/message/JYZGIDEBV4R5E7XXT3KFS2O545TDTAGT/
Code of Conduct: http://python.org/psf/codeofconduct/

Reply via email to